Forest evapotranspiration dynamics over a fragmented forest landscape under drought in southwestern Amazonia

Ongoing climate change and human conversion of forests to other land uses alter regional evapotranspiration dynamics and, consequently, impact associated hydrological systems in Amazonia. We studied the effects drought fragmentation on forest using surface energy balance-based model METRIC (Mapping Evapotranspiration at high Resolution with Internalized Calibration) for a fragmented landscape Brazil's Amazonian state Rondônia. Dry season (June-August) estimates were produced 2009-2011 period that encompassed 2010 event, one extreme droughts Amazon. data analyzed relation (monthly precipitation cumulative water deficit) (edge distance from 100m 1000m edge density). During dry 2009, pre-drought, did not fall below 110mm/month. However, year showed drastic decline by 32%, 75mm/month, July August. In 2011, rates still depressed August dropping as low 85mm/month. Forest driven mainly corresponding deficits drier years (2010 2011), although along edges fragments locally significant, scale. The near (to 100m) had progressively lower levels than interior seasons progressed these differences greatest year, reaching almost 5%. Our results suggest during driest months, exacerbated both rate extent reductions over areas up edges, equivalent ~20% forested our study area.